Patent document 1 describes, in order to evaluate life of equipment subjected to creep fatigue damage, calculating plastic strain increments Δεp based on strain that occurs under conditions where the load exerted on the equipment is fluctuating; calculating creep strain increments Δεc based on increments of strain that occurs under conditions where the load exerted on the equipment is steady; calculating fatigue damage φp using the Δεp; calculating creep damage φc using the Δεc; and evaluating life of equipment.
Patent document 2 describes, in creep crack growth assessment, analyzing temperature and stress using input information and analysis data on temperature and stress in a database; analyzing creep crack growth life using the information obtained by the analysis, data of non-destructive inspection, and data obtained by the analysis of creep crack growth life; and judging the time to replace components for high-temperature apparatus from the information obtained by the analysis.